I know that Mathematica isn't built to model 3D, but most of my models are equation-defined so here's my question: is it somehow possible to combine ad-hoc 3D objects as well as ordinary/parametric/closed-form 3-dimensional plots into a single rendering?

I know about the ability to export and recombine elsewhere, but I don't want to do that right now. (Also, for some reason, SolidWorks crashes when importing complicated models.)

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